ST. PETERSBURG — Backed by residents of other St. Petersburg neighborhoods, a group of Snell Isle homeowners has won a battle to keep developers from building two big houses on what now is a single lot.

But the fight is likely to go on.

Julianne and Thomas Frawley say they expect to appeal the denial of their request to split their lot on Rafael Boulevard NE so they can sell it as two buildable lots.

On Wednesday, the city's Development Review Commission rejected the Frawleys' request for a variance after speakers from Snell Isle, Allendale and the Old Northeast complained that developers are putting up disproportionately large homes in some of the city's most attractive neighborhoods.

"It already has resulted in irreversible change of character and loss of beauty," said Brian Smith, who lives in Allendale.

Snell Isle resident Dede Murtagh, a retired professional engineer, said she is not opposed to development. But many new homes cover so much of their lots that "you're getting almost a townhouse-like feel," she said.

The Frawleys sought a variance to split their lot into two 60-foot lots — each 15 feet less than the minimum width allowed on Snell Isle.

By knocking down the existing 50-year-old house, developers would be able to build two "beautiful new homes," Thomas Frawley told commissioners. If sold for $850,000 each, about the average price for new construction on Snell Isle, they would generate an additional $24,000 in property tax revenues each year, he said.

But neighbors noted that the two houses would be next to two other McMansions built during a period when city zoning codes permitted new construction on substandard-size lots.

"Two oversized homes were built in 2012 and 2014, respectively, on the first two non-conforming lots on Rafael Boulevard west of Appian Way," Elizabeth Stiles said. "If this variance is approved, there would be four such homes in a row on Rafael."

She and others argued that street-side parking would increase in front of the four homes due to their limited driveway space. Other neighbors said approving the variance would change the character of what is now a quiet, brick-paved street beloved for its large lots with spacious lawns.

"That's what attracted me to this neighborhood 15 years ago," Steven Hart said. "I used to live in Southern California and saw where the neighborhood started to change quickly, very quickly. It resulted in wall-to-wall street parking."

Last September, the St. Petersburg City Council changed back the zoning code to restrict development on substandard lots. Anyone seeking to split a lot into undersized parcels now must get a variance.

In considering the Frawleys' request, city staffers did a survey of the entire Snell Isle neighborhood that found the average lot size is 90 feet with 82 percent of all properties conforming to that size. As a result, the staff recommended denying the variance on the grounds that building two homes would be "injurious" to neighbors and inconsistent with "the existing pattern of development."

The commissioners' vote to deny was 6-1, with only Commissioner Chris Scherer supporting a variance. He noted that before last year's zoning change, the Frawleys could have split the lot to allow construction of two homes.

"I think it is a confiscation of property rights," Scherer said of the vote to deny the variance.

The Frawleys, who have had several developers interested in their property, can appeal the decision in circuit court.